#!/usr/bin/env python
# -*- coding:utf-8 -*-
# @FileName  :if_10.py
# @Time      :2020/6/22 10:32
# @Author    :Administrator

a = float(input('请输入一个数：'))
print('正数') if a > 0 else print('零') if a == 0 else print('负数')

# if a > 0:
#     print('正数')
# elif a == 0:
#     print('零')
# else:
#     print('负数')
